Re: [PATCH v2 2/2] cpuhp: Expedite RCU grace periods during SMT operations

[kernel test robot <lkp@intel.com>]

Hi Vishal,

kernel test robot noticed the following build errors:

[auto build test ERROR on next-20260213]
[also build test ERROR on linus/master]
[cannot apply to tip/smp/core rcu/rcu/dev v6.19 v6.19-rc8 v6.19-rc7 v6.19]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Vishal-Chourasia/cpuhp-Optimize-SMT-switch-operation-by-batching-lock-acquisition/20260216-202247
base:   next-20260213
patch link:    https://lore.kernel.org/r/20260216121927.489062-6-vishalc%40linux.ibm.com
patch subject: [PATCH v2 2/2] cpuhp: Expedite RCU grace periods during SMT operations
config: alpha-allnoconfig (https://download.01.org/0day-ci/archive/20260217/202602170042.5jdtaQeu-lkp@intel.com/config)
compiler: alpha-linux-gcc (GCC) 15.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260217/202602170042.5jdtaQeu-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202602170042.5jdtaQeu-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from kernel/rcu/update.c:50:
>> kernel/rcu/rcu.h:515:20: error: static declaration of 'rcu_expedite_gp' follows non-static declaration
     515 | static inline void rcu_expedite_gp(void) { }
         |                    ^~~~~~~~~~~~~~~
   In file included from include/linux/rbtree.h:24,
                    from include/linux/mm_types.h:11,
                    from include/linux/mmzone.h:22,
                    from include/linux/topology.h:34,
                    from include/linux/irq.h:19,
                    from include/asm-generic/hardirq.h:17,
                    from arch/alpha/include/asm/hardirq.h:8,
                    from include/linux/hardirq.h:11,
                    from include/linux/interrupt.h:11,
                    from kernel/rcu/update.c:25:
   include/linux/rcupdate.h:1193:13: note: previous declaration of 'rcu_expedite_gp' with type 'void(void)'
    1193 | extern void rcu_expedite_gp(void);
         |             ^~~~~~~~~~~~~~~
>> kernel/rcu/rcu.h:516:20: error: static declaration of 'rcu_unexpedite_gp' follows non-static declaration
     516 | static inline void rcu_unexpedite_gp(void) { }
         |                    ^~~~~~~~~~~~~~~~~
   include/linux/rcupdate.h:1194:13: note: previous declaration of 'rcu_unexpedite_gp' with type 'void(void)'
    1194 | extern void rcu_unexpedite_gp(void);
         |             ^~~~~~~~~~~~~~~~~


vim +/rcu_expedite_gp +515 kernel/rcu/rcu.h

2b34c43cc1671c Paul E. McKenney        2017-03-14  509  
25c36329a30c8c Paul E. McKenney        2017-05-03  510  #ifdef CONFIG_TINY_RCU
25c36329a30c8c Paul E. McKenney        2017-05-03  511  /* Tiny RCU doesn't expedite, as its purpose in life is instead to be tiny. */
7414fac050d5e0 Paul E. McKenney        2017-06-12  512  static inline bool rcu_gp_is_normal(void) { return true; }
7414fac050d5e0 Paul E. McKenney        2017-06-12  513  static inline bool rcu_gp_is_expedited(void) { return false; }
6efdda8bec2900 Joel Fernandes (Google  2023-01-12  514) static inline bool rcu_async_should_hurry(void) { return false; }
7414fac050d5e0 Paul E. McKenney        2017-06-12 @515  static inline void rcu_expedite_gp(void) { }
7414fac050d5e0 Paul E. McKenney        2017-06-12 @516  static inline void rcu_unexpedite_gp(void) { }
6efdda8bec2900 Joel Fernandes (Google  2023-01-12  517) static inline void rcu_async_hurry(void) { }
6efdda8bec2900 Joel Fernandes (Google  2023-01-12  518) static inline void rcu_async_relax(void) { }
2be4686d866ad5 Frederic Weisbecker     2023-10-27  519  static inline bool rcu_cpu_online(int cpu) { return true; }
25c36329a30c8c Paul E. McKenney        2017-05-03  520  #else /* #ifdef CONFIG_TINY_RCU */
25c36329a30c8c Paul E. McKenney        2017-05-03  521  bool rcu_gp_is_normal(void);     /* Internal RCU use. */
25c36329a30c8c Paul E. McKenney        2017-05-03  522  bool rcu_gp_is_expedited(void);  /* Internal RCU use. */
6efdda8bec2900 Joel Fernandes (Google  2023-01-12  523) bool rcu_async_should_hurry(void);  /* Internal RCU use. */
25c36329a30c8c Paul E. McKenney        2017-05-03  524  void rcu_expedite_gp(void);
25c36329a30c8c Paul E. McKenney        2017-05-03  525  void rcu_unexpedite_gp(void);
6efdda8bec2900 Joel Fernandes (Google  2023-01-12  526) void rcu_async_hurry(void);
6efdda8bec2900 Joel Fernandes (Google  2023-01-12  527) void rcu_async_relax(void);
25c36329a30c8c Paul E. McKenney        2017-05-03  528  void rcupdate_announce_bootup_oddness(void);
2be4686d866ad5 Frederic Weisbecker     2023-10-27  529  bool rcu_cpu_online(int cpu);
474d0997361c07 Paul E. McKenney        2021-04-20  530  #ifdef CONFIG_TASKS_RCU_GENERIC
e21408ceec2de5 Paul E. McKenney        2020-03-16  531  void show_rcu_tasks_gp_kthreads(void);
e0a34641eb551e Arnd Bergmann           2023-06-09  532  #else /* #ifdef CONFIG_TASKS_RCU_GENERIC */
e0a34641eb551e Arnd Bergmann           2023-06-09  533  static inline void show_rcu_tasks_gp_kthreads(void) {}
e0a34641eb551e Arnd Bergmann           2023-06-09  534  #endif /* #else #ifdef CONFIG_TASKS_RCU_GENERIC */
e0a34641eb551e Arnd Bergmann           2023-06-09  535  #endif /* #else #ifdef CONFIG_TINY_RCU */
e0a34641eb551e Arnd Bergmann           2023-06-09  536  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki